Answer and Explanation:
1. The journal entries are shown below:
a. cash Dr $640,000
      To Short term note payable  $640,000
(Being signing of note payable is recorded)
b. Equipment Dr $14,750
    To cash $14,750
(being equipment purchased on cash is recorded)
c. Supplies Dr $17,800
    To account payable $17,800
(being inventory purchased on account)
d. Repairs and Maintenance expense Dr $26,900
      To Cash $26,900
(being cash paid is recorded)
e. Cash Dr $74,000
    To Unearned revenue $74,000
(being cash is recorded)
f. Cash Dr $97,200
    To Service revenue $97,200
(Being service revenue is recorded)
g. Cash Dr $750
    To Unearned revenue $750
(being cash is recorded)
h. Account payable Dr $8,900 (50% of $17,800)
    To cash $8,900
(Being cash paid is recorded)
i. Salaries & wages expense Dr $26,500
    To cash $26,500
(being cash paid is recorded)
2. The net income is
= Â Revenue - expenses
= $97,200 - $26,900 - $26,500
= $43,800